studies electrical and electromagnetic methods for

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Studies of Electrical and Electromagnetic Methods for Characterizing Salt Properties at the WIPP Site, New Mexico

C. K. Skokan, M. C. Pfeifer, G. V. Keller, H. T. Andersen Dept. of Geophysics Colorado School of Mines Golden, Colorado 8040 1

Prepared by Sandia National Laboratories Albuquerque New Mexico 87 185 and Livermore California 94550 for the United States Department of Energy under Contract DE AGO4 76DP00789

Printed June 1989

._ . . -- _--_-I. .

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STUDIES OF ELECTRICAL AND ELECTROMAGNETIC METHODS FOR CHARACTERIZING SALT PROPERTIES

AT THE WlPP SITE, NEW MEXICO

C.K. Skokan, M.C. Pfeifer, G.V. Keller, and H.T. Andersen Dept. of Geophysics

Colorado School of Mines Golden, Colorado 80401

ABSTRACT

At the Waste Isolation Pilot Project Site in southeastern New Mexico, technical and engineering issues related to the long-term storage of hazardous wastes in bedded salt are being studied. For nuclear waste repositories with both long operational periods (50 yr) and long performance assessment periods (10000 yr), the Disturbed Rock Zone (the zone of rock in which the mechanical and hydrologic properties have changed in response to excavation; abbreviated as DRZ) is important to both operational (e.g., slab or fracture failure of the excavation) and long-term performance (e.g., seal system performance and fluid transport). Because of the large contrast in electrical conductivity between crystalline salt and salt saturated with water, it is to be expected that electrical geophysical methods may play an important role in delineating portions of the DRZ. The Colorado School of Mines, under contract to Sandia National Laboratories, has carried out experimental surveys using the direct current electrical method and two electromagnetic methods underground in the mine workings. The results suggest that the various electrical methods are effective in locating low resistivity zones in the salt, which probably represent moisture-rich zones. Furthermore, it appears that such measurements might well be further optimized in terms of survey effort and design of systems to provide a high response to small-scale conductive features in the salt.

i

ACKNOWLEDGMENTS

The authors wish to thank Dr. David Borns and Sandia National Laboratories in Albuquerque, New Mexico for their assistance and financial support. Dan Garber of Sandia National

Laboratories is thanked for his assistance in getting the manuscript ready for publication.

.. 11

CONTENTS

BACKGROUND .............................................................. 1

IN-MINE ELECTROMAGNETIC SURVEYS ......................................... 3

IN-MINE ELECTRICAL (DC) MEASUREMENTS ..................................... 7 Experimental Setup .................................................... 7 Apparent Resistivity with a Uniform Earth As a Reference ...................... 7 Apparent Resistivity with a Three-Layer Reference Earth ....................... 10

CONCLUSIONS ............................................................. 16

REFERENCES .............................................................. 17

Figures

1 . Stratigraphic Section for the WlPP Site ......................................... 2

2 . Location Map of EM-3 and EM-31 Traverses in the WlPP

3 . Plot of Conductivity vs . Distance for EM-31 Data Recorded

4 . Conductivity vs . Distance in E140 from S3700 to S2100 forEM-31 ............................................................ 5

5 . Histogram of Conductivity for Drift N1100 Measured with theEM-31 ............................................................ 5

6 . Conductivity WI . Station Number for the EM.34, Recorded in Drift N1100 between E140 and E1540 with a 20-meter Loop

7 . Relationship between Apparent Resistivity and Water Content for Different Factors of Concentration Showing Ranges for Resistivity and Water Contents .......................................... 6

8 . Location Map for DC Resistivity Measurements .................................. 8 9 . Typical DC Recording ...................................................... 8 10 . Cumulative Conductance vs . Depth for WlPP 22 Resistivity Log .................... 9 11 .TheThree-.yerModel ..................................................... 11 12 . Electric Field Curve for ThreeLayer Earth ..................................... 11 13 . Total Potential Curve for Three-Layer Earth .................................... 12 14 . Potential Curves for Line Sources A and B ..................................... 12 15 . TheSpecificThree-LayerModel ............................................. 14 16 . Distribution of Apparent Resistivities in ohm-m for

Three-Layer Earth ..................................................... 14

Underground Workings ................................................ 4

inDriftNllOObetweenE140andE15 40 .................................... 4

Separation ........................................................... 6

... 111

...... ....... - . ....... I- .. _lll .......... . . . . . . . . . .- . . .

STUDIES OF ELECTRICAL AND ELECTROMAGNETIC METHODS FOR CHARACTERIZ- ING SALT PROPERTIES AT THE WlPP SITE,

NEW MEXICO

Background

The Waste Isolation Pilot Plant (WIPP), located 23 miles east of Carlsbad in southeastern New Mexico, is being constructed in part to evaluate engineering and technical problems associated with the long- term storage of nuclear waste in bedded salt. The facility is being constructed in rocks of the Salado .Formation of Permian age (see Figure l), at a depth beneath the surface of approximately 650 meters. The Salado For- mation is part of a 1.2-km-thick layered evaporite sequence in the Delaware Basin of southeastern New Mexico (Powers et al., 1978; Barrows and Fett, 1985). Rock units of interest in this report are Ochoan, with the ex- ception of the underlying Delaware Mountain Group (DMG). The oldest Ochoan unit is the Castile Formation, which overlies the Bell Canyon Formation of the DMG (Figure 1). Lo- cally, the Castile consists of three anhydrite units separated by two halite units. Above the Castile stratigraphically is the Salado For- mation, which consists of halite, anhydritic and/or polyhalitic halite, and argillaceous halite. Overlying the Salado is the Rustler Formation, which contains siltstones, an- hydrites, dolomitic siltstones, dolomites, and halite.

At the WlPP Site, the beds are almost flat, dip- ping to the southeast at only 10 meters per kilometer. Locally, deformation has produced anticlines in the Castile and lower Salado formation (Borns et al., 1983). Portions of the Rustler and Dewey Lake formations may ex- hibit local zones of dissolution, breccia pipes, joints, and fractures (Barrows and Fett, 1985). Underground at the WlPP Site within the Salado Formation, fractures within salt

1

and anhydrite, and zones of brine influx have been observed from the excavation. The characterization of these fractures and zones of brine influx is important to the evaluation of operational (e.g., slab or fracture failure of the excavation) and long-term performance (e.g., seal system performance and fluid transport) of the WIPP Site. Therefore, in order to guide both construction and performance assessment, it is essential that the capability for detecting and mapping fractures and brine concentration in salt be developed.

The rock property which is most sensitive to the presence of water is the electrical resistivity (or conductivity, which is the reciprocal of resistivity, and the units for conductivity [millisiemens] and resistivity [ohm-m] are used interchangeably). Pure (anhydrous) rock salt is an insulator, having a resistivity of thousands of a-m (Lishman, 1961). On the other hand, evaporite sequences with thin layers of anhydrite and a high content of hygroscopic salts have a resistivity of tens to hundreds of a-m (Kessels et al., 1985). The electrical resistivity of evaporites appears to obey Archie's law relating bulk resistivity to water content:

PO a

4) - 4N =m

where: Po = the resistivity of the rock h v = the resistivity of the pore fluid a = a constant 4) = the porosity m = the cementation factor.

As a consequence, water contents as low as a few hundred parts per million (by weight)

W t I- -I

c7 z o-30 Blanket and dune rands. lag gravels. 3 channel rands.

<-75 Cross-bedded. medium-to-coarse-gralned

90-170 Reddish-orange. gyplllerOuI rlltstone.

90-140

sandstone.

Bedded halite. anhydrlte. and s~ltstones Broken by two areally persistent dolomite members .

530-600 Mostly halite Wilh interbedded anhydrnte. polyhallte. and clayey Io silty CIastiCs

Three masswe laminated anhydntelcalclte uwtr separated by two massive halite units wim anhydrite interbeds

380

Fine-gramed randstone, siltstone. and shales with limestone interbeds.

Figure. t Stratigraphic Section for the WlPP Site

will affect the bulk resistivity of pure salt markedly, as will water contents as low as 1000 or 2000 ppm in the less pure sequence of evaporites.

Electrical resistivity or conductivity is a diag- nostic property in salt for detecting the presence of even small amounts of water, re- quiring only that an accurate and operable method for measuring resistivity (or conductivity) in place is available. Because of the oil and gas deposits in the vicinity of the WIPP Site, as well as the commercial deposits of evaporated minerals, extensive efforts to measure the resistivity of the section have been made over the past half-century. More recently, studies of resistivity have been carried out in conjunction with the GNOME ex- periment carried out by the U.S. Atomic Energy Commission (Keller, 1962), and with development of the WlPP Site using conventional electrical and electromagnetic methods

on the Earth's surface (Washburne and Sternberg, 1985). On the basis of past work, it appears feasible to detect fractures and brine concentrations in the salt using these surface- based su rve yi n g techniques. However, the question remains as to how well such features can be detected if the survey- ing methods were optimized to the problem of detecting small conductive features in layered salt. The Department of Geophysics at the Colorado School of Mines (CSM) un- dertook a study of exploration methods using very general forms of transmitter and receiver arrays operating underground. The results of these field measurements were an evaluation of the survey approach, in terms of both sensitivity to small features in the salt, and evaluation of the compatibility of the survey technique with ordinary mine operations and constraints.

2

IN-MINE ELECTROMAGNETIC SURVEYS

The initial phase of the CSM study was the use of conventional electromagnetic coupling equipment of short range to make measurements of the electrical resistivity of wall rock in the tunnel openings at the WlPP Site. Two systems were used: the EM-31 and EM-34 systems manufactured by Geonics, Ltd., of Toronto, Canada. In both systems, the mutual coupling between two induction coils is measured and converted to apparent resistivity using self-contained analog computation circuits. With the EM-31 system, the two coils are separated by a distance of 3 meters and energized at a frequen- cy of 10 kHz. In the EM-34 system, the two induction coils are separated by 20 meters, and energized at one of two frequencies (6.4 or 1.6 kHz). The distance of search for the two instruments is 1 to 2 meters (for the EM- 31) or 10 to 20 meters (for the EM-34).

Measurements were carried out with the EM- 31 equipment along lines in drift NllOO between station E140 and E3000, in drift E300 between stations S400 and S2100, and in drift E140 between stations S3700 and S2100. Readings were made at intervals of 3.2 or 7.6 meters along these intervals. Locations are indicated on a map of the WIPP Site in Figure 2.

Two profiles of resistivity measurements made with the EM-31 equipment are shown in Figures 3 and 4. Apparent resistivities are the integrated resistivity of the volume of rock interogated by the system. Also, since conductivity is the reciprocal of resistivtty, the two are used interchangeably. Measured conductivities range generally from 200 to 1000 n-m (1 to 5 millisiemens per meter). A distribution (histogram) of the conductivities measured with the EM-31 equipment is shown in Figure 5. This histogram shows that

the bulk conductivity (the reciprocal of resistivity) near the tunnels is between 2.0 and 2.5 millisiemens per meter with some areas having a higher resistivity of approximately 3.25 millisiemens per meter.

A single profile was measured with the EM- 34. These measurements were recorded in Drift NllOO as the first EM-31 profile (Figure 6). This profile was measured in NllOO as a comparison of the EM-31, and was used as a control to test the accuracy of the EM-31. In the case of the EM-34, measured conductivities ranged from 7 to 10 millisiemens per meter (resistivtty from 100 to 140 n-m).

The deeper measurements (with the EM-34) show a conductivity several times larger than those measured with the EM-31 equipment. This may reflect an alteration in the conductivity of the rocks forming the walls of the tunnels, which are dried by the warm air of the ventilation system. Such a dried rind was observed by Keller(1962) in measurements made on the walls of tunnels in rhyolitic tuff at the Nevada Test Site.

The EM-34 gives much more uniform values than the EM-31. The EM-34 has a larger depth of penetration (up to 20 meters) so that it uses a larger rock volume to derive its resistivity than does the EM-31 (up to 4 meters). Because of this, the EM-31 is more able to detect small zones of higher or lower conductivity near the tunnels.

in Figure 7, the EM-31 and EM-34 resistivities are compared with the data Kessels et al. (1985) obtained from salt mines in Germany. Based on this comparison we expect the water content of the salt around the mine openings to increase from 0.8 to 1.0% (by weight) near the surface to between 2 and 3% at a depth of several meters.

3

EXPERIMENTAL

I , I , I , I 1 I I I 1 I (

-

.. . = ...

Figure 2. Location Map of EM-31 and EM-34 Traverses in the WlPP Underground Workings

. . . . ..... ... .. . . . . . . . .-. . . . .. . . ..... ". .. .. .. .... ........ 0 . 5 ... . . . . . . . . . .. . . . . . . . . .. ..I ....

8 e . . ..

I I I 1 1 1 I I I

c10 cl5 co c5

STATION NUMBERS

Figure 3. Plot of Conductivity vs. Distance for EM-31 Data Recorded in Drift N1 100 between E140 and E1540

4

6.0

5.0

4.0

3.0

2.0

1 .o

0.0

. .' . . .. .... Z . . . . . . . " ... ..... . . * " .'. .. ". ..e..*. .. .. . -+- an:... . - .

.*

.. "

.. .. ... .*.: . . .

.. 1 # , , 1 , , , 1 { , ( , , 1

s1 s5 s10 sl5

STATION NUMBERS

20

15

K W

10 3 z

1.5 2.0 2.5 3.0 3.5 4.0 4.5

CON DU CTl VI TY (mill isiemendmeter)

Figure 5. Histogram of Conductivity for Drift NllOO Measured with the EM-31

5

Figure 4. Conductivity vs. Distance in E140 from S3700

I I I 1 I I I

5.0

11.0

>

3.0

I 1 I I I I I I I I I 1 I I

0 .

I 1 I I I I I I I I I 1 I I

0 .

0 0 .

..* 0 . 0 .....- 0 .

0

I I I I I I I I I I I

cl c5 ClO c15 cl c5 ClO c15

STATION NUMBERS

Figure 6. Conductivity vs. Distance in El40 from S3700 to S2100 in Drift N110 between El40 andE1540 with a 20-meter Loop Separation

107

L

!! w 103 a u)

10’ 0,001 0.01 0.1 1.0 10.0

WEIGHT % H20

Figure 7. Relationship between Apparent Resistivity and Water Content for Different Factors of Concentration Showing Ranges for Resistivity and Water Contents

6

IN-MINE ELECTRICAL (DC) MEASUREMENTS

A major effort consisted of making electric field and electric potential measurements in the mine openings with a source of direct current sited on the surface, using a generalized resistivity mapping approach. Receiver locations are shown in Figure 8.

Experimental Setup

The rocks around the mine workings were energized using a fixed dipole source located on the earth's surface immediately to the north of the underground workings. Well casings extending to a depth of about 300 meters were used as electrodes; the two wells were located about 1 .O kilometer apart. The primary power supply used for this pur- pose was a 27-KVA, gasoline-engine- powered electrical generator. The AC output was converted to DC and switched at intervals of 4 s, to reverse the direction of current flow. The peak-to-peak level of the reversals in current to the source electrodes was nominally 200 amperes, though the level varied by about IO%, depending on line heat- ing. Switching of the current to the source electrodes was controlled by a precision clock.

For the underground measurements, a tem- porary laboratory was established underground for the operation of a Digital Equipment Corporation MlNC 11/23 computer as a data recording device. Voltages developed in the rock exposed in the mine were detected using pairs of copper/copper sulfate half-cells held against the rock forming the wall or floor of the tunnel at a measurement site. At each measurement site, four measurements were made; three of these were made with half-cells separated by 2 meters, and a fourth measurement was made

7

of the voltage drop between one half-cell at the measurement site and another reference half-cell near the underground laboratory. For the three measurements made with half- cell pairs separated by two meters, it was assumed that the ratio of voltage difference to separation was approximately equal to the electric field component along the direction of separation. The fourth measurement was taken to be the potential at the recording site, by adding to it a reference potential from the half-cell at the underground laboratory.

The voltage from a pair of half-cells was amplified with a battery operated amplifier at the measurement site, before transmitting it over a twisted pair of wires to the underground laboratory. At the laboratory, the sig- nal from the measurement site was converted to digital form with 12-bit resolution, and recorded on a flexible disc by the MlNC 1 1 /23 computer. Each reversal of the electric field or potential was sampled 1024 times, using a second precision clock to synchronize the recording interval with the transmitter. A typical record of a voltage reversal is shown in Figure 9. A total of 135 measurements was made at the 45 sites indicated in Figure 8.

Apparent Resistivity with a Uniform Earth as a Reference

In DC electrical surveys, the first step in interpretation is usually the computation of an apparent resistivity; often such an apparent resistivity is similar in magnitude to the rock resistivity and can be used directly in evaluat- ing the electrical properties of the rock in which the measurements were made. The usual definition of apparent resistivity is that it is the resistivity for a uniform half-space (a reference earth) that would have lead to the observation of the same voltages as were ac-

137 90

199 10 122 70 183 70

212 1 101 3 159 0

Figure 8. Location Map for DC-Resistivity Stations and Measured Apparent Restivities

(5 c U

I i -

-1 . 257

Flgure 9. Typical DC Recording

8

tually observed in the real, usually in- homogeneous earth. Often, this apparent resistivity is viewed as a weighted average of the resistivities actually existing in the earth, with the weighting depending on how much of the excitation current enters any given part of the earth with a given resistivity. For a four- point array, the apparent resistivity can be calculated as:

where AM, AN, BM, and BN are the distan- ces between the source electrodes A or B and the receiver electrodes M or N, V is the voltage measured between M and N and I is the current driven between A and B.

Calculations using Eq. 1 are based on an assumption that current flows from each of the well casings as though each were a point

electrode on the surface. Whether or not this is a reasonable assumption can be evaluated as follows. Flow of current from the length of casing at each well was simulated as ten in- dividual flows from sections of casing at ten points along its extent. The location of these points and the fraction of current flowing in each was determined from the resistivity well log obtained in the well before casing. This resistivity log was integrated over the depth of each well to provide the conductance vs. depth curve shown in Figure IO. This curve has the character of a series of nearly straight-line segments, each segment repre- senting an interval with relatively uniform resistivity. To simulate the full casing, it was assumed that a point electrode was located at each midpoint of an interval characterized by a straight-line segment. The amount of current assigned to each such point electrode was in proportion to the portion of the total conductance contributed by each layer. Equation (1) was again used to compute apparent resistivity, but in place of two

I 1 I I I I I I I I I I

. WIPP-22 RESISTIVITY LOG

r

0.0 0.2 0.4 0.6 0.8 1 .o 1.2

DEPTH (feet x 103)

Figure 10. Cumulative Conductance vs Depth for WlPP 22 Resistivity Log

9

point electrodes, 20 point electrodes were used as sources. The differences found with this more exact approach were not over- whelming, though some values were changed up to 2oor6. The distribution of apparent resistivity values was determined for the principal direction of the electric field. The range of apparent resistivities (tens and hundreds of n-m) appears as low for salt. However, this is due to definition of apparent resistivity used to charac- terize the salt. The definition assumes that the current entering the salt must have the same density as it would in a uniform earth. In fact, the current from the sources spreads through the more conductive surface layers of rock, with the current density flowing into the underlying salt being very low in comparison with that in a uniform earth. As an ex- treme case, if salt might be perfectly insulating, then no current would flow from the surface layer into the salt, the measured electric field would be zero, and the com- puted apparent resistivity would be zero. Be- cause of this, we have chosen to define apparent resistivity in terms of a three-layer reference model, described in the next section.

Apparent Resistivity with a Three-Layer Reference Earth

Since the current entering the salt at the Rustler/Salado contact does not have the same current density as a model based on a uniform distribution of resistivities as dis- cussed above, apparent resistivities are not accurately calculated by Equation (1) alone. Therefore, we have developed a three-layer model to compute apparent resistivity and to account for the stratigraphy at WlPP (Figure 11). The surface layer is characterized by a conductance (SI: the ratio of thickness [tq] to resistivity pi]), and is ener-

gized by vertical line electrodes (the well casings) providing a current, I, to the earth. The second layer is characterized by a transverse resistance, T2 (product of thickness, h2, and resistivrty, pz). The third layer is assumed to have negligible resistivity (well logs show that the third layer has a resistivity less than 10 n-m). The three layers ap- proximate the Rustler Formation (water-bearing), the Salado/Castile Formations (salt and anhydrite-bearing) and the Bell Canyon For- mation (water-bearing), respectively.

With this model the electric field and the potential at the surface of the earth and at the surface of the second layer are virtually the same if the resistivrty of the second layer is much greater than the resistivity of the surface layer. The potential at the bottom of the salt layer is about zero because of the high resistivity. Knowing the potential at the top and bottom of the salt layer, one then can predict the magnitude of the electric field within the salt merely by dividing the potential drop by the thickness of the salt. This re- quires knowledge of the conductance of the surface layer and of the transverse resistance and thickness of the salt.

The electric field on the surface can be com- puted using well-known methods (Keller and Frischknecht, 1966). For the model assumed here the electric field will at first decrease in inverse proportion to distance from a single well casing:

E(r) = 1, 2lrrs3

where r is the distance from casing to observation point, I is current, and SI is the conductance of the surface layer. At some large distance such that the area for vertical leakage of current from the first layer to the

10

TWO VERTICAL LINE SOURCES OF CURRENT

I S l = h , P l LAYER 1

CALCULATED

'61 E-F1ELD VECTOR LAYER 2 P = ? T2= h, P2

LAYER 3 P = O

Figure 11. The Three-Layer Model

RESISTIVITY RANGE - 70 to 500 ohm-m

I I I I 1 I I I I I I I I I , 2.4 2.6 2.0 3.0 3.2 3.4 3.6 3.0 4.0

LOG DISTANCE (meters)

Figure 12. Electric Field Curve for a Three-Layer Earth

11

101

100

10-1

10-2

i t RESISTIVITY RANGE - 70 to 500 ohm-m

\ 4

t I 1 I I l l I 1 I I I I

103


Figure 13. Total Potential Curve for Three-Layer Earth

POTENTIAL FIELDS (volts) MODEL #I RES-70 RES-500

I 1 1 1 I I I I I 1 I I 1

0 s -3

-4

-5 1000 2000 5000


Figure 14. Potential Curves for Line Source A and B

12

third layer becomes adequate, the electric field will begin to fall rapidly with increasing distance (see Figure 12).

The potential, which is the quantity that we wish to know at the top surface of the salt, is found by integrating an electric field curve similar to the one shown in Figure 12 from in- finity inwards to the point r, where the potential is to be evaluated. Because we have two vertical line sources, the net potential is the difference of the contribution from each (Figure 13). The potential was obtained by numerical integration and is shown by the curves in Figure 14.

In arriving at an apparent resistivity (Pa,2) for a three-layer reference earth, the following expression is used:

13

T2Eo Pa,2 = (3)

h2Er

where Er is the reference electric field, Eo is the observed electric field, and Pq2 is the resistivity assumed for unit 2 ( "a,2 is specified once values of T2 and h2 are assigned).

Values of apparent resistivity were calculated based on a specific three-layer reference model (Figure 15). The distribution of values is shown in the histogram of apparent resistivities in ohm-m (Figure 16). The high apparent resistivities (lo3 to lo4 ohm-m) are measured near the heated rooms, and the lower resistivities (10 to lo3 ohm) are measured away from the heated rooms at the facility horizon. These values are in general agreement with EM-31 values, again indicat- ing a bulk water content in the salt of about 2% by weight.

LAYER 1

LAYER 2

I S, = hl/Pl = 3.56 *OS ,

LAYER 3 P = O

Figure 15. The Specific Three-Layer Model

I- z 3 0 u w a z a a

30-100 100-300 300-1000 1000-3000 3000-10000 10000-30000

RESISTIVITY RANGES (ohm-meter)

Figure 16. Distribution of Apparent Resistivites in omh-m for a Three-Layer Earth

14

CONCLUSIONS

From all of the data obtained the bulk water content is between 1 and 3% by weight. The methods used are shallow (0 to 10 m) inves- tigative tools which may be used to detect wet zones or water-filled fractures near the tunnels. This may be of importance in characterizing the development of fractures around

the excavations and delineating possible pas- sageways for migration of introduced and formation water around the storage facilities. The next step in interpretation of the data is numerical modeling to simulate conductive anomalies in the vicinity of the tunnels.

15

REFERENCES

Barrows, L, and J. Fen, 1985. A high-precision gravity survey in the Delaware Basin of Southeastern New

Borns, D. J., L J. Barrows, D. W. Powers, and R. P. Snyder, 1983. Deformation of Evaporites near the Waste

Keller, G.V., 1962. Electrical Properties of the Earth's Crust, Part 2; Earth voltages observed during the GNOME

Kdler, G.V., and F. C. Frischknecht, 1966. Electrical Methods in Geophysical Prospecting, Pergamon, Oxford,

Kessels, W., I. Flentge, and H. Kdditz, 1985. DC geoelectric sounding to determine water content in the salt mine

Lishman, J.R., 1961. Salt bed identification from unfocused resistivity logs, Geophysics, vol. 26, no. 3, pp. 320-

D. W. Powers, S. J. Lambert, S. E. Shaffer, L R, Hill, and W. D. Weart, eds, 1978. Geological Characterization

Mexico: Geophysics, vol. 50, no. 5, pp. 825-833.

lsolation Pilot Plant (WW) Site, SAND@-1 069 (Sandia National Laboratories, Albuquerque, NM)

explosion, USGS Open File Report, Project 8100.

517 pp.

ASSE (FRG), Geophysical Prospecting, vol. 33, no. 3, pp. 436-446.

341.

Report, Waste lsolation Pilot Plant (WPP) Site, Southeastern New Mexico, Vds 1 and 2, SAND78-1596 (Sandia National Laboratories, Albuquerque, NM.)

Laboratories, Phoenix Geophysics Washburne, J. and B. K. Stemberg, 1985. Final Report: Electrical Surveys of WIPP-12 Site for Sandia National

16

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U.S. Geological Survey Branch of Regional Geology Attn: R. Snyder MS913, Box 25046 Denver Federal Center Denver, CO 80225

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U.S. Geological Survey Conservatlon Division Attn: W. Melton P.O. Box 1857 Roswell, NM 88201

U.S. Geological Survey (2) Water Resources Division Attn: Cathy Peters Suite 200 4501 Indian School, NE Albuquerque, NM 871 10

U.S. Nuclear Regulatory Commission (4) Division of Waste Management Ann: Michael Bell

Hubart Miller Jacob Philip NRC Library

Mail Stop 623SS Washington, DC 20555

Environmental Evaluation Group (3) Attn: Library Suite F-2 7007 Wyoming Blvd., N.E. Albuquerque, NM 87109

New Mexico Bureau of Mines and Mineral Resources (2)

Attn: F. E. Kottolowski, Director J. Hawley

Socorro, NM 87801

NM Department of Energy & Minerals Attn: Kasey LaPlante, Librarian P.O. Box 2770 Santa Fe, NM 87501

Battelle Pacific Northwest Laboratories (6) Attn: D. J. Bradley

J. Rdyea R. E. Westerman S. Bates H. C. Burkholder L Pederson

Battelle Boulevard Richland, WA 99352

Battelle Engineering Development Section OWTD Attn: C. 6. Brumleve 7000 South Adams Street Willowbrook, Illinois 60521

Savannah River Laboratory (6) Attn: N. Bibler

E. L Albenisius M. J. Plodinec G. G. Wicks C. Jantzen J. A. Stone

Aiken, SC 29801

Savannah River Plant Attn: Richard G. Baxter Building 704-S Aiken, SC 29808

George Dymmel SAC 101 Convention Center Dr Las Uegas, NV 89109

INTERA Technologies, Inc. (4) Attn: G. E. Grisak

J. F. Pickens A. Haug A. M. LeVenue

Suite #300 6850 Austin Center Blvd. Austin, TX 78731

INTERA Technologies, Inc. Attn: Wayne Stensrud P.O. Box 2123 Cartsbad, NM 88221

IT Corporation (2) Attn: R. F. McKinney

J. Myers Regional m ice - Suite 700 5301 Central Avenue, NE Albuquerque, NM 87108

IT Corporation (2) Attn: D. E. Deal P.O. Box 2078 Cartsbad, NM 88221

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Los Alamos Scientific Laboratory Attn: B. Erdal, CNC-II Los Alamos, NM 87545

Oak Ridge National Laboratory (4) Ann: R. E. Blanko

E. Bondietti C. aaibome G. H. Jenks

Box Y Oak Ridge, TN 37830

RE/SPEC, Inc. Attn: W. Coons

P. F. Gnirk P.O. Box 14984 Albuquerque NM 87191

RE/SPEC, Inc. (7) Ann: L L Van Sambeek

D. 8. Blankenship G. CaHahan T. Pfeifle J. L Ratigan

P. 0. Box 725 Rapid Ci, SD 57709

Rockwell International (1) Attn: C. E. Wickland Rocky flats Plant Gdden.CO 80401

Rockwell International (3) Atomics International Division Rockwell Hanford Operations Attn: J. Nelson (HWVP)

P. Salter W. W. Schuttz

P.O. Box 800 Richland, WA 99352

Science Applications International Corporation Attn: Howard R. Pratt,

10260 Campus Point Drive San Diego, CA 92121

Senior Vice President

Science Appfications International Corporation Attn: Michael B. Gross

Suite 1250 160 Spear Street San Francisco, CA 94105

Ass?. Vice President

Systems, Science, and Software (2) Attn: E. Peterson

Box 1620 La Jdla, CA 92038

P. Lagus

Westinghouse Electric Corporation (7) Attn: Library

W. C. Moff i W. P. Poirer W. R. Chiquelin V. F.Likar D. J. Moak R. F. Kehrman

P. 0. Box 2078 Carlsbad, NM 88221

University of Arizona Attn: J. G. McCray Department of Nuclear Engineering Tucson, AZ 85721

University of Arizona (2) Attn: J. J. K. Daernen

B. K. Sternberg Dept. of Mining and Geological Engineering Tuscon. AZ 85721

Colorado Schod of Mines (10) Department of Geophysics Attn: C. K. Skokan 1500 Illinois Street Golden, Colorado 80401

University of New Mexico (2) Geology Department Attn: D. G. Brookins

Library Albuquerque, NM 87131

Pennsylvania State University (1) Materials Research Laboratory Attn: Della Roy University Park, PA 16802

Texas A&M University Center of Tectonophysics College Station, TX 77840

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The University of Texas at Austin Attn: Priscilla P. Nelson

Kenneth H. Stokoe Dept. of Civil Engineering Austin, Texas 7871 2

G. Ross Heath College of Ocean and Fishery Sciences University of Washington Seattle, WA 98195

Thomas Brannigan Library Attn: Don Dresp, Head Librarian 106 W. Hadley St. Las Cruces, NM 88001

Hobbs Public Library Attn: Ms. March Lewis, Ubrarian 509 N. Ship Street Hobbs,NM 88248

New Mexico State Library Attn: Ms. Ingrid Vollenhofer P.O. Box 1629 SantaFe,NM 87503

New Mexico Tech Martin Speere Memorial Library Campus Street Socorro, NM 87810

Pannell Library Attn: Ms. Ruth Hill New Mexico Junior College Lovington Highway Hobbs,NM 88240

Roswell Public Library Attn: Ms. Nancy Langston 301 N. Pennsylvania Avenue Roswell,NM 88201

WlPP Public Reading Room Attn: Lee Hubbard, Head Librarian Carlsbad Municipal Library 101 S. Halagueno St. Carlsbad,NM 88220

Government Publications Department General Library University of New Mexico Albuquerque, NM 87131

NATIONAL ACADEMY OF SCIENCES. WlPP PANEL

Dr. Charles Fairhurst, Chairman Department of Civil and

University of Minnesota 500 Pillsbury Dr. SE Minneapolis, MN 55455

Mineral Engineering

Dr. John 0. Blomeke Route 3 Sandy Shore Drive Lenoir C i , TN 37771

Dr. John D. Bredehoeft Western Region Hydrologist Water Resources Division US. Geological Survey (M/S 439) 345 Middlefield Road Menlo Park, CA 94025

Dr. Karl P. Cohen 928 N. California Avenue Palo Alto, CA 94303

Dr. Fred M. Ernsberger 250 Old Mill Road Pittsburgh, PA 15238

Dr. Rodney C. Ewing Department of Gedogy University of New Mexico 200 Yale, NE Albuquerque, NM 87131

Dr. William R. Muehlberger Department of Geological Sciences University of Texas at Austin P.O. Box 7909 Austin, TX 7871 2

Dr. Frank L Parker Department of Environmental Engineering Vanderbilt University Nashville, TN 37235

Dr. D’Arcy A. Shock 233 Virginia Ponca City, OK 74601

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Dr. Peter B. Myers, Staff Director National Academy of Sciences Committee on Radioactive

2101 Constitution Avenue Washington, DC 20418

Waste Management

Staff Officer Board on Radioactive Waste

Management GF462

2101 Constitution Avenue Washington, D. C. 20418

Studiecentrum V w r Kemenergie Centre D'Energie Nucleaire Attn: Mr. A. Bonne SCWCEN Boeretang 200

BELGIUM 8-2400 M d

Atomic Energy of Canada, Ltd. (2) Whiteshell Research Estab. Attn: Peter Haywood

John Tait Pinewa, Manitoba, CANADA ROE ILO

Dr. D. K. Mukerjee Ontario Hydro Research Lab 800 Kipling Avenue Toronto, Ontario, CANADA M U 5S4

Mr. Jean-Pierre Olivier OECD Nuclear Energy Agency Division of Radiation Protection

38, Boulevard Suchet 7501 6 Paris, FRANCE

and Waste Management

Claude Sombret Centre D'Etudes Nucleaires De La Vallee Rhone CENNALRHO S.D.H.A. BP 171 30205 Bagnds-Sur-Ceze FRANCE

Bundesministerium fur Forschung und Techndogie Postfach 200 706 5300 Bonn 2 FEDERAL REPUBLIC OF GERMANY

Bundesanstalt fur Geowissenschaften und Rohstoffe Ann: Michael Langer Postfach 510 153 3OOO Hannover 51 FEDERAL REPUBLIC OF GERMANY

Hahn-Mietner-lnstitut fur Kernforschung Attn: Werner Lutze Glienicker S t r a w 100 100 Berlin 39 FEDERAL REPUBLIC OF GERMANY

lnstitut fur Tieflagerung (4) Attn: KKuhn Theodor-Heuss-Strasse 4 D-3300 Braunschweig FEDERAL REPUPLIC OF GERMANY

Kernforschug Karlsruhe (1) Attn: K. D. Closs Postfach 3640 7500 Karlsruhe FEDERAL REPUBLIC OF GERMANY

Physikalisch-Technische Bundesanstalt Attn: Peter Brenneke Postfach 33 45 D-3300 Braunschweig FEDERAL REPUBLIC OF GERMANY

D. R. Knowles Briiish Nuclear Fuels, plc Risley, Warrington, Cheshire WA3 6AS 1002607 GREAT BRITAIN

Shingo Tashiro Japan Atomic Energy Research Institute Tokai-Mura, Ibaraki-Ken 319-1 1 JAPAN

Netherlands Energy Research Foundation ECN (2) Attn: Tuen Deboer, Mgr.

L. H. Vons 3 Westerduinweg P.O. Box 1 1755 ZG Petten, THE NETHERLANDS

Svensk Karnbransleforsorjning AB Attn: Fred Karlsson Project KBS Kambranslesakerhet Box 5864 10248 Stockholm, SWEDEN

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Sandia Internal: 1510 J. W. Nunziato 1520 C. W. Peterson 1521 R. D. Krieg 1521 J. G. Arguello 1521 H. S. Morgan 3141 S. A. Landenberger (5) 3151 W. I. Klein (3) 3154-1 C. H. Dalin, (8) for DOE/OSTI 6OOO D.LHartley 6230 W. C. Luth 6232 W. R. Wawersik 6233 T. M. Gerlach 6233 J.LKrumhansl 6300 R.W. Lynch 6310 T. 0. Hunter 6313 T. Blejwas 6330 W. D. Weart 6330 V. L Bruch 6330 S. Pickering 6331 A. R. Lappin 6331 R. L Beauheim 6331 D. J. Borns (10) 6331 P. B. Davies 6331 S. J. Lambert 6331 R. Z. Lawson 6331 K. L Robinson 6331 M. D. Siege1 6332 LD.Tyler 6332 R. Beraun 6332 B. M. Butcher 6332 B. L Ehgartner

6332 6332 6331 6332 6332 6332 6332 6333 6334 6334 6334 6334 6334 6334 6334 6334 6334 6334 6334 71 00 7110 71 20 71 25 71 25 71 30 71 33 71 33 71 35 8524

M. A. Mdecke D. E. Munson J. Nowak

R. J. Roginski J. C. Stormont T. M. Torres Sandia WlPP Central Files (800GEOPH) (10) T. M. Schultheis D. R. Anderson S. Bertram-Howery K. Brinster L Brush M. S. Y. Chu L S. Gomez R. Guzowski R. L Hunter M. G. Marietta R. R. Rechard A. Rutledge C. D. Broyles J. D. Plimpton M. J. Navratil R. L Rutter J. T. Mcllmoyle J. 0. Kennedy 0. Burchett J. W. Mercer P. D. Seward P. W. Dean (SNLL Library)

f? U S GOVERNMENT PRINTING OFFICE 1989-673-049/81052

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studies electrical and electromagnetic methods for

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